Compiler optimizations are done in both intermediate code and generated machine code. So what is it like when we compile the project? Earlier in the chapter, when we discussed the preprocessing of the source code, we looked at a simple structure containing several source files, including two headers, rect.h and square.h, each with its .cpp files, and main.cpp, which contained the program entry point (the main() function). After the preprocessing, the following units are left as input for the compiler: main.cpp, rect.cpp, and square.cpp, as depicted in the following diagram:
The compiler will compile each separately. ...
